The turbulent history of Szczecinek reaches back to the High Middle Ages, when the area was ruled by Pomeranian dukes and princes. The majority of the city's architecture survived World War II and, subsequently, its entire Old Town was proclaimed a national heritage monument of Poland.

In 1310, the castle and town were founded under Lübeck law by Duke Wartislaw IV of Pomerania and modelled after Szczecin (German: Stettin) which is situated about 150 kilometres (93 miles) to the west. The initial name was "Neustettin" (Polish: Nowy Szczecin, German: Neustettin, Latin: Stetin Nova). It was also known as "Klein Stettin" (Polish: Mały Szczecin, German: Klein Stettin). In 1707 the town was known in Polish as Nowoszczecin, while the Mały Szczecin name gradually developed into the modern name Szczecinek.[1]

The town was fortified to face the Brandenburgers, with a wall and palisades. In 1356 Neustettin was hit by the plague. Thankful for their survival, the Dukes Bogislaw V, Barnim IV and Wartislaw V founded the Augustine monastery Marienthron, on the Mönchsberg on the southern bank of Lake Streizigsee. Under the Duke Wartislaw VII Neustettin, from 1376 to 1395 it was the seat of his Duchy. Afterwards, it was ruled by Pomeranian Duchy: Rügenwalde (-1418), Wolgast (-1474) and Stettin (until 1618).

On 15 September 1423, the "great day of Neustettin", the Pomeranian dukes, the Hochmeister of the Teutonic Order and Nordic king Eric VII of Denmark met to discuss defense against the union of Brandenburg and Poland. In 1461 Neustettin was sacked, looted and burned by Polish troops and Tatars because King Casimir IV wanted to take revenge on Eric II of Pomerania-Wolgast who supported the Teutonic Knights.

In 1881 Abraham Springer, great-grandfather of TV presenterJerry Springer and a prominent member of the town's Jewish community launched an unsuccessful attempt to sue agitator Dr Ernst Henrici, claiming that an inflammatory anti-semitic speech in the town led directly to the burning down of the synagogue on 18 February of that year.[2]

In 1945, the Red Army occupied the town and put it under Polish administration. The totality of the town's native population, being German, was expelled and arriving Polish citizens took their place and property.